lib/sema.txt
author Edouard Tisserant
Fri, 08 Mar 2013 11:38:26 +0900
changeset 801 8255f1a371d7
parent 251 5e7457efbb8f
permissions -rw-r--r--
Stripped generated files again. http://stackoverflow.com/questions/3290908/which-files-generated-by-autotools-should-i-keep-in-version-control-repository
(*
 * (c) 2011 Edouard Tisserant
 *
 * Fake semaphore support, for non preemptive implementation.
 *
 *)


FUNCTION_BLOCK SEMA
  VAR_INPUT
    CLAIM : BOOL;
    RELEASE : BOOL;
  END_VAR
  VAR_OUTPUT
    BUSY : BOOL;
  END_VAR
  VAR
    Q_INTERNAL : BOOL;
  END_VAR

  Q_INTERNAL := CLAIM OR ( Q_INTERNAL AND (NOT RELEASE));
  BUSY := Q_INTERNAL;

END_FUNCTION_BLOCK